Consider the following card game:
A set of nine cards numbered 1 to 9. Two players in turns pick up a card. The winner is the player who first have three of his cards add up to 15.
For instance, in the fourth turn Player A gets 1,2,3,9 and Player B gets 4,5,6,7, then Player B wins the game as 4+5+6=15.
Better have a try first before continue to read.
Three classes of 1-9 tiles in Mahjong. [Source: Wikimedia Commons]
If we talk about an IQ game involving 1 to 9, which game comes to your mind?
Let me guess: the magic square! Arrange the nine cards in a magic square.
Now plays the card game again.
Have you noticed that you are just playing Tic-Tac-Toe?
It is a game that you may already dismiss as too childish long time ago.
Old thing can be new again if it is given a completely different look.